Adsorbents, such as active carbons, which are generally used in particulate form in industrial adsorption processes tend as a rule to form dusts, particularly under mechanical load, as occur, for example, during filling into adsorption apparatuses or especially during use in an agitated bed. The abrasion occurring under such a mechanical load may present serious problems in further process steps; in particular, abrasion of this type may make it virtually impossible to use many particulate adsorbents in an agitated bed. To avoid these disadvantages, U.S. Pat. No. 4,535,005 has provided a process for the consolidation of the surfaces of the particulate adsorbents, in which from 25 to 90% of the adsorbents is first covered with water and then heated at a temperature at which the adsorbed water evaporates and, as long as absorbed water evaporates, is treated with aqueous dispersions of self-crosslinking copolymers, with mixing, and the copolymers are then crosslinked with heating at 110.degree.-180.degree. C.. However, this process is relatively energy-consumptive and furthermore has the disadvantages that the adsorbents are immersed beforehand in water and polymer dispersions rendered specifically heat-sensitive and containing reactive groups are employed.
Furthermore, U.S. Pat. No. 4,535,004 discloses a process for the consolidation of the surfaces of particulate adsorbents, in which the adsorbent, which initially contains virtually no water, is treated with an aqueous suspension of filament-like structures of self-crosslinking copolymers, the filament-like structures being deposited on the surfaces of the adsorbent, the water absorbed by the adsorbent being evaporated and the adsorbent covered with the filament-like structures being heated to 110.degree.-180.degree. C. and the copolymers crosslinking. This process, which is likewise energy-consumptive, furthermore has the disadvantage that some of the filament-like structures are removed from the adsorbent by abrasion by mixing in a running drum and non-uniform layers are thus obtained.